75 million???
Im not really into richy rich things, Id buy a modest home and some acrage proabably in TENN on Watts Bar Lake. A speed and bass boat, Make sure every member in good standing of the family is taken care off say a million each. so that leaves about and put a couple million away for emergencies.
That would leave about 68 million. Id definately have to try a year of racing in a sprinter proabably USAC/MSCS and then hire a under rated gun like Westfall or Cone for a few years.
Id probably buy up some old big factory suitable and have indoor 3/8th or maybe combo quarter-half mile track that we could have a winter racing series in. seat maybe 20,000 and pay for itself eventually.
You'd need a job? You'd have a job but it wouldn't be charity. Grind some tires darn it

.
Oh and a Bell Turbo helicopter with bed, mini kitchen. I LIVE IN TENN and have to make all the IND-USAC-MSCS shows possible!
I'd probably play a little JW Hunt as well and do some purse boosting for certain races.
Chuck, broke again and selling everything off fifteen years from now.